Generally, devices for manufacturing wire harness used in vehicles such as automobiles are comprised of: a means for cutting long electric wire in a predetermined length; a means for stripping jacket on both ends of the electric wire; a means for crimping the end of the electric wire to a terminal; and a means for inserting the terminal crimped to the electric wire in a connector housing. (e.g., refer to Patent Documents 1-3).
For example, such prior art wire harness manufacturing device is comprised of an electric wire terminal crimping device as shown in FIG. 10.
The electric wire terminal crimping device is comprised of: an electric wire measuring section 80 for measuring the electric wire; a stripping section 100 for stripping jacket on both ends of the electric wire; a terminal crimping section 60 for crimping the terminals at the ends of the electric wire; a terminal-position regulating section 70 for regulating the posture of the terminal; and a terminal-inserting section 110 for inserting the terminal attached wire in a connector housing.
In such an electric wire terminal crimping device, the electric wire 140 is fed a predetermined amount at the electric wire measuring section 80 and the electric wire 140 is sent into a U-turn mechanism (not illustrated), and thereby, terminal at the downstream end of the electric wire 140 is made to do a U-turn and then held with the electric wire holding hand 101. Thereafter, the electric wire 140 is measured and is driven at the electric wire measurement section 80, and after the measurement ends, the electric wire 140 is cut by a cutter 90 and its terminal at the upstream end is held with the electric wire holding hand 101. At this point, both ends of the electric wire 140 which underwent measurement and cutting are held with the electric wire holding hand 101 and the wire forms a U-shape. The wire is then conveyed to respective process sections by means of an electric wire conveying method which will be described later.
Jackets on both ends of the U-shaped electric wire 140 are stripped off at the stripping section 100 and the terminals are then crimped to the ends at the terminal crimping section 60. A plurality of pressing device 60a is provided in the terminal crimping section 60 so as to enable the crimping of a plurality of types of terminals that configure the wire harness. Upon crimping the terminals, the electric wire holding hand 101 crimps the terminals by advancing the tip of the electric wire 140 inside the pressing device 60a by means of the distance adjusting mechanism 160 that adjusts the strokes of the air cylinder 150 as shown in FIGS. 11(A) and (B). FIG. 11(A) shows a situation before advancing the tip of the electric wire 140 whereas FIG. 11(B) shows a situation after advancing the tip.
Position of the terminal-attached electric wire 140a having the terminals which have been crimped is fixed in up-down and left-right directions by the terminal-position regulating section 70 and transferred to the terminal-inserting hand 110a. The terminal-inserting hand 110a is a robot having the X-Y-Z axes and it inserts the terminals of the terminal-attached electric wire 140a in the connector housing 130 which is placed in the connector receiving jig 120 positioned in the terminal-inserting section 110.
In the following, method of conveying the electric wire 140 to each process section mentioned above will be described.
The electric wire 140 held with the electric wire holding hand 101 is held with the electric wire conveying hand 103 placed on the electric wire conveying hand unit 102 provided in a parallel direction to each process section described above such as the electric wire measurement section 80, and the electric wire holding hand 101 releases the electric wire 140. Then, after an actuator 50 (e.g., air cylinder) moved the electric wire for a distance corresponding to the installed pitch of the process sections, the electric wire holding hand 101 grips the electric wire 140 once again. Then, the electric wire conveying hand 103 releases the electric wire 140 and the actuator 50 returns to its original position. Thus, the pitch conveyance of the electric wire 140 is carried out by means of the operation of grip-substituting the electric wire and the intermittent operation of the actuator 50.    Patent Document 1: Japanese Patent Application JP 06-223646 A1    Patent Document 2: Japanese Patent Application JP 07-29662 A1    Patent Document 3: Japanese Patent Application JP 07-240121 A1